Fighters loyal to Muammar Gaddafi, who now control just one small area of Sirte, are making their final stand in the toppled Libyan leader's hometown.
It is thought there are about 2,000 fighters left there.
They have been pushed back as the frontline has moved in recent days, but they are still offering strong resistance, and National Transitional Council [NTC] forces had to draw back slightly on Thursday because of heavy shelling.
The NTC fighters have been suffering casualties, and with each one the anger and resentment deepens.
Most of that is directed at the foreign fighters. Anyone black is considered to be one of Gaddafi's hated mercenaries.
Al Jazeera's Tony Birtley reports from Sirte.